is WPG really accurate? plus DIY CO2 question

This is a discussion on is WPG really accurate? plus DIY CO2 question within the Beginner Planted Aquarium forums, part of the Beginner Freshwater Aquarium category; -->
I was surfin around on the internet when I stumbled on this page-
http://www.rexgrigg.com/mlt.html
It proposes that Lux per Square Inch (LSI) is more ...

How much light would I really need for a 10 gal? I'm asking because I'm about to order some high-light plants and want to be prepared.
Regardless, would two 23W cool white CFLs (in a 10 gal) be enough light to grow pretty much anything?

I plan on researching this a bit by placing them all in my main tank with 2 23w cfls and then moving the cuttings to my other tank with a measely 20 watts of light to see if they live.

Also, would that lower the PH significantly? I have livebearers- they like a slightly basic tank. A difference of .4 would be okay, but nothing more.
If so I'll hook the Co2 to a planted fishless tank just to grow the plants out for possible resale.

I know this post wasn't organised very well, so..
1. LSI or WPG?
2. How many watts for a 10gal with "high light" plants
3. Yeast method of co2 enrichment- waste of time? Will it influence PH significantly?

A well planted 10g needs about anywhere from 7-14 watts (that's what mine had for yrs now and I'd wanna say my tank pictures in the log speak for themselves)
If you were to put some 50watts over a 10g you'd literally fry the plants (no joke!).

What is important in planted tanks is the spectrum, being a full spectrum and the Kelvin which ideally should be around 5-6500K.

Why do you need co2? If you have fish in the tank that's all you need!?

Plants won't amend your pH; but over/using CO2 sure would.

YOu may want to read the sticky's up top from Byron its a series of 4 that explain in all details what your plants need.

Feel free to check out my aquarium log here on the left under my name; all these tanks you see there are well planted; Lights from the homestore and no CO2 added and no ferts....

Also remember that the smaller the tank the less accurate WPG is. Espescially in tanks 10g and under. I am running 3WPG in my 10g and that is doing medium/high plants for me, but I wouldn't attempt any high light plants in it.

Well realistically you can scrap the whole WPG matter to a certain extent; cause the WPG in itself does not take into account:
Are you dealing with T8's or T5's or CFL's or regular bulbs.......all this makes a big difference too.

Well realistically you can scrap the whole WPG matter to a certain extent; cause the WPG in itself does not take into account:
Are you dealing with T8's or T5's or CFL's or regular bulbs.......all this makes a big difference too.

I was thinking Cool white 6500k CFLs. maybe two 18watt would be plenty? The plants I'm considering are considered high-light plants.

Oh please, no offense to who ever told you these are high light needing plants; but my Hygro & Rotals sit in THE dimmest tank I have ever had with like less then 0.5 wpg and they're exploding; the Rotala I have to trim at least 2" per week to keep it under the surface; same issue with the Sagittaria.

Rex Grigg, while I don't know him personally, is the kind of person I like. He was a Marine, shoots from the hip, doesn't take crap, and knows his stuff. He also smokes cigars. And he may be correct about LUX.

But one thing to keep in mind is there are some forums that are drastically focused on high tech co2, super high light tanks. Many tropical plants grow in dimmer lit waters because of the natural cloudiness of the water. Aquarium plants will do well in lower light. Look and Angel's and Byron's tanks for proof.

If you start jacking up the lights with high outputs and the like you're going to have to feed the plants more. Both with fertilizers and co2. I for one do not wish to fertilize every day. That's a lot of cash over time. I think of it like this. These high tech tanks and all the gadgets and fooling is kind of like the soft handed yuppie with a Harley. He has one but rides it a couple times a year. But he can say he has one. Oooooh look at my super glorious lush tank that went from this to jungle in a month. Don't get me wrong. I'm not bashing high tech. I'm saying you don't need the Harley to have fun motorcycling. Get my drift?

This chap is very good and his articles are very dense, heavy on the technical side and I find a challenge to read; however, his articles on lighting, UV sterilizers, and Redox are some of the very best around. I find I have to print out his articles and read them a couple of times:

I am glad to see the WPG rule is finally starting to be ruled out. I have preaching for years at how out of date the rule is in relation to todays lighting systems. We use all low tech approaches to our planted tanks. The main thing to consider is the spectrum. Go with a daylight 6500k -10,000k bulb. We use 1-2 23 watt 6500k cfl daylight bulbs on a 10 gallon. One bulb will easily grow low to medium plants. 2 will grow just about any plant out there. Layer the substrate with soil a few nails (iron) and hardware store bought pea gravel on top.(contains natural metals and minerals) And no need for fertilizers should be needed unless a high plant load is used. Only then minimal fertilizer will be needed.
HTH
Dan

I'm gonna kinda go with Rex on this one (got my regulator and dry ferts from him anyway) Lux will be more accurate than WPG. Its not as easy to use though, nor is it the best. PAR is the best way you can determine how plant friendly your lights are. This is much more difficult though, PAR meters are very expensive I know they are used by some people like Tom Barr for experimenting with lighting. For the most part we are suck to using data others have collected. With a PAR meter for example you can not only test specific brands of bulbs, you can also determine what reflectors work the best testing both material and shape.

I agree with the other link that LED's will most likely be the future of our lighting. As a broke college student I'm still waiting for them to drop in price. I intend to make a DIY fixture eventually, but currently your still looking at ~$100 to light a 20 gal tank.